sdm845-common: udfps: Update handler with newly introduced methods

Just stubs, at least for now.

Change-Id: Iff5604b35368ad5f417265df4e2eaf5a09ff7d74

udfps/UdfpsHandler.cpp

@@ -77,6 +77,15 @@ class XiaomiUdfpsHander : public UdfpsHandler {
     void onFingerUp() {
         // nothing
     }
+
+    void onAcquired(int32_t /*result*/, int32_t /*vendorCode*/) {
+        // nothing
+    }
+
+    void cancel() {
+        // nothing
+    }
+
   private:
     fingerprint_device_t *mDevice;
 };